Problem: If $x \veebar y = 4x-y$ and $x \diamond y = 4x-7y$, find $-6 \veebar (0 \diamond 2)$.
Answer: First, find $0 \diamond 2$ $ 0 \diamond 2 = (4)(0)-(7)(2)$ $ \hphantom{0 \diamond 2} = -14$ Now, find $-6 \veebar -14$ $ -6 \veebar -14 = (4)(-6)-(-14)$ $ \hphantom{-6 \veebar -14} = -10$.